This is not possible out of the box. However, you can do this easily with my PageBuilder plugin.
1) create a 'link' type page, setting 'Display Permissions' to 'Registered Users', set 'Build Static' to 'No'.
2) link to this 'link' type page, instead of the built in detailed page. The URL will be: page.cgi?page=<page_name>;link=<link_id> (replace <page_name> with the 'Page Name' of the page you defined in 1) and <link_id> with the ID of the link.
I hope this helps.
Ivan
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Iyengar Yoga Resources /
GT Plugins